Fixture for removing bonded brake lining from brake shoes



AJg- 10, 1954 P. E. FLENER ET AL 2,685,925

FIXTURE FOR REMOVING BONDED BRAKE LINING FROM BRAKE SHOES Filed Feb. 9, 1949 UNITED STATE-S Patented Aug. 10, 1954 FIXTURE FOR REMOVING BONDED BRAKE LINING FROM BRAKE SHOES Application February 9, 1949,' Serial'No.':75,368

yATENT OFFICE 5 Claims.

. This invention relates generally to an improved apparatus adapted for the removal of brake lining from a brake shoe to which the lining has previously been bonded.

A primary object of the invention resides in the provision of a universally -adjustablejand manuallyY operable mechanism for the rapid removal of ribbon-like brake lining from anarcuate surface of a brake shoe to which it has previously been adhesively bonded.

It is common practiceto attach brake lining of the type.A normally employed in the automobile industry to a brake shoe, for example of the internally expanding type, both by means of a plurality of rivets and by means of an adhesive bonding agent, in the absence of rivets. If rivets are employed, they normallyv extend through the brake lining with the rivet heads countersunk below the peripheral surface of the lining, and also through a flange-like portion ofthe brake shoe providing backing support for the lining. During a brake relining operation, it is merely necessary to chisel off .theserivetsandfremove the worn lining preparatory-to the application of new lining, and since thisoperation is a relatively simple one, itis customarily accomplished manually.

The use of adhesive bonding agents has, however, yreplaced to a large extentthe useof rivets since-certain advantages-residein the elimination ofrivets. For example, wearonthe complementarybrake drum is reduced, since the lining may be Worn practically downto the surface of the shoe without metal-to-metalcontact between the shoe andthe drum. Adhesive bondingby means of greatlyimproved bonding agents of the .type developed during .the last ten years,

results in an improved shoe and( lining .unit resembling integral construction. '.Riveted lining is maintainedin clamped engagement with the shoe only through vthe immediate area of the rivet heads, hence there is. present relativeplay between portions of the. liningand corresponding portions of the shoe which may result, 'during the normal life Vofthe lining, in a loosening of the rivets and hence a lgeneral. loosening. of the lining upon the shoe. Y

"While it has beenv generally conceded that a greatly improved bond results from the use of ,the newly developed adhesive bonding agents rather than .rivets .for theapplicationof brake lining to brake shoes, a serious Vdisadvantage heretofore residedin the fact that'adhesivelyapplied lining Wasextremely'diicult toiremove. It is common practice for a `workman to'clamp' the brake' shoe in'a'bench vise andjremove the* lining', :bit by bit,

`2 byuse of a hand. chisel and hammer. This work proves both Atedious and time-consuming, and since the toolf'is not always held at a proper-angle, it'requires frequent sharpening. Since complete relining of passenger automobile brakes requires theremoval of lining from eight shoes, the time consumed `in the removal of lining, and hence the attendant expense, vis considerable.

It is to the relief of this condition that the present invention primarily'is directed.

A further object ofthe invention isy to provide an improved manually operable device, readily adjustable for the reception oi' brake shoes of varying sizes-for the rapidv alignment and rigid mounting thereof in` a manner whereby the entire lining may rapidly be separated from an associatedshoe through asimple rotational operation which may be `conducted manually.

A stil-l further objectof the invention resides in the provision oi-.anrapparatus adapted for the rapid removal oi `brake lining from an associated shoe Without injury to the supporting surface of the shoe -to which the lining is adhesively bonded.

A'still further object resides in the provision f of anapparatus of universal applicationl which may.- be simply but accurately adjusted forremoval'of the lining from shoes of varying sizes.

Another objectof thek invention isk to provide a simple but rugged brake lining removal apparatus which may be marketed` to sell at a price attractive to such customers as small garages and repair shops.

Other objects and vadvantages are generally to improve and simplifyv brake. lining removing apparatus while effecting the above stated objects. Further objects and advantages will become rapparent to persons skilled in the art upon examination of the,drawings, the description, and the claims appended thereto.

ln the drawings, in which like parts are identilied by the same reference numerals,

Fig. l is a perspective view of a brake lining removing apparatus incorporating the principles of the present invention and illustrating its method ofr use, with a brake shoe clamped therein and aportion of the lining shown removed from. the shoe;

Fig; 2 is a planview of the device of Fig. 1 but with the brake shoe removed to best illustrate the construction of the apparatus;

Fig; 3 is a fragmentary View in vertical section taken-aleng line S4-3 oi Fig.' 2; and

*Fig 4 is a fragmentary View in vertical section taken along line -Le of Fig. 2.

' As best shown in Fig. l, the device includes a base plate it, preferably of' metal such as cast iron or steel but which may be of other material such as hardwood. Base plate IB provides a generally planate top surface I I and stepped side margins I2 if desired, to facilitate mounting on the surface of a suitable support member such as a work bench by means of bolts or screws I3. Base plate It provides support for the rotational mounting thereon of a manually operable carriage member I5 by means of a suitable pintle IE, the lower end of which is xed to member I0, in any suitable manner, not shown, to extend vertically therefrom and through a suitable aperture, not shown, provided in carriage I5. Pintle IE preferably includes an upper shank portion Il', a hexagonal portion I8 for the reception of a wrench, and a lower cylindrical portion of a length substantially equal to the thickness of the carriage member I5 through which the shank portion extends.

The lower cylindrical portion of pintle I6, which provides journaled support for the carriage member I5, leads in turn into a diametrically reduced threaded section adapted for screwthreaded engagement with a suitable internally threaded bore provided in base member I0. The nut I8 permits tightening of the pintle into clamped engagement with base member I to a sufcient degree to prevent loosening of the pintle during normal use. The pintle is designed to permit no appreciable axial movement of carriage member I between the upper surface II of base member I8, and the lower surface of nut I8, between which carriage I5 is confined.

Carriage i5 is preferably constructed of metal, such as steel, but as in the case of base member ID, material such as hard wood may also be employed. In actual practice it has been found desirable to construct base member Ill of cast iron and carriage l5 of a suitable grade of steel. Carriage I5 includes a head portion 29 for the support of clamp units 2l and 22 and a handle portion 2t which may be an integral extension of head portion. 2Q or detachably engaged in respect thereto. Head portion 20 may be provided with a circular margin 25, preferably extending, in concentric relation to pintle I6, through an arc of approximately 180. The circular marginal portion of carriage I5 leads at one end into a reduced neck portion 28 of handle 24, and at the other end into a truncated margin 29 leading in a substantially direct path to reduced neck 2S. Margin 29 provides support adjacent circular margin 253 for a lug type stop member 30, clamped by Allen head screws 3l to extend outwardly oi circular margin 255 a sucient distance to provide a stop member against which one end of a brake shoe is abutted for the purpose of constraining the shoe against circumferential movement during operation of the apparatus.

Clamp units 2i and 22, the construction of which is best shown in Fig. 4, are identical and are radially disposed, in approximate 90 angularity, in respect to p-intle I6. The angular relation of these units is of course not critical, and will depend somewhat upon the most common type of brake shoe to be processed. The most common type of passenger automobile brake shoe extends through an arc of somewhat less than 180 and this type of shoe may be securely supported with the clamping units angularly disposed as shown. Each clamping unit 2| and 22 is partially disposed in upwardly open channels 32 and 33 provided in carriage I5. Referring in detail to the construction of unit 22, Fig, 4, a pair of ringer-like clamp elements 3B and 31 are maintained at the radially inward end thereof in pinned engagement by means of a dowel Din Si! pressed into suitably aligned bores. Element 3'. presents a planiiorm surface, while element 3S is provided with a contour surface to provide a channel between the two members into which the inwardly directed mounting flange 52 of the brake shoe is receivable.

A suitable bore is provided in element for a helical spring iii, maintained under compression intermediate elements 3% and 3l' to urge element 36 outwardly from element 3l to an extent permitted by a clamping bolt 9.2, including an Allen type head Ml, a shank portion t6 extending through suitable bores provided in elements 35 and 3l, and through an elongate slot el leading downwardly from slot 35i in carriage I5, into a third elongated slot t8 opening at the lower surface of carriage t5. Slots di' and Ll, in common with slot 33, have longitudinal axes positioned to extend radially in respect to pintle I5. The lower end of bolt 2 is threaded for the reception of a nut of a dimension substantially greater than the width of slot il? and suiiciently great to prevent rotation ci nut $5 within slot fill.

With bolt 42 loosened, radial adjustment of clamp unit 22 is permitted within limits defined by the radial distance of slot lll. With the device designed for use with passenger oar size brake linings, slot lil is of suflicient length to permit universal adjustment within the tolerances of variation normally found in passenger car brake shoes. The construction of clamping unit 2l is of course identical with the construction of clamp unit 2i above described.

With a brake shoe E@ with worn lining 5I to be removed therefrom, maintained clamped on carriage I5 by means of clamp units 2l and 2i?, carriage I5 and the brake shoe 5@ may be rotated about an adjustably positionable knife assembly 54 for the rapid removal of lining from the shoe.

Knife assembly 5i! includes a block-like knife supporting member 55 slidably adjustable within a guideway 5'! extending longitudinally of base plate IIB as viewed in Figs. l and 2. Block 55 is provided with a diagonally disposed surface 58 offset at 59 for the reception of a cutter blade 5I! in usli relation thereto, said cutter blade 6@ being detachably engageable in respect to block 55 by means of a pair of set screws 52 extending through suitable bores at right angularity to cutter blade Sii. Screws 52 threadedly engage cutter blade 60 and are preferably partially countersunk within block 55. Angular adjustment of cutter blade til, to permit tangential disposition of the blade in respect to the outer surface of brake shoe 50 is effected in the following manner.

A guide member 54 includes a base portion 65 corresponding in thickness to the depth of guideway 5l and complementally receivable therein. Base portion is integral with a rectilinear upper portion 56 provided with a horizontally disposed set screw 61 extending therethrough and. adapted to engage blo-cl; 55. Bloch 55 is provided with a vertically extending bore 'Ill for the reception or" a set screw 'Il extending therethrough, through a registered bore 'l2 in base portion 65 of block 64, an elongate slot 'Ill leading downwardly from guideway 5l to base plate Iii, and into a lower elongate slot 'l5 into which slot 'Irl leads. Slot 'I5 is of greater width than slot 'M and adapted for the reception of a rectangular nut I6 of greater dimension than the width of slot 74 and of a size to be restrained against turning Within Slot I5 while permitting, with set screw escasas 'II loosened, adjustment `Ar-of1"*k'nife assemblfd along guideway-'t'sl '"Since'thbaseof blocki`55` is supported 'onth'e upper-faceoffbase 65fof block 64 `a1; fthe/'level of 'the surface of base :plats i`I-Il, block 55, andhence vknife :'maybef rotated about setscrew i'I I toobtain'theuesired degreeofangularity in respect' to'the' brake shoe. Setscrew Sjnding itssupport'in'slidable 'but nonsro'tatable"block""64, 'providesrastop to`l limit counterclockwise rotation of block 55. The assembly is so positioned that the cutting edge of blade 60 is in tangential relation to the circumferential surface of brake shoe 50.

As an aid to establishing concentric alignment of brake shoe 50 in respect to pintle I6, an adjustable scribe arm 8U is mounted on pintle I6 for Y radial adjustment in respect thereto. A cap 8| is mounted for free rotation in respect to pintle I6, and is provided with a diametric bore for the reception of a partially flattened shank portion 82 of scribe arm 30. A set screw 84 is threaded axially into cap 8| to engage the at of shank 82set screw 84 being of the knurled knob type to provide rapid manual adjustment of scribe arm Eil. Scribe arm 86 is preferably provided with depending pointed end 85 which is shown in registry with one of a plurality o1" scribe lines 86, provided upon the upper surface of base plate I in concentric relation to pintle I6 for the purpose of aiding in the initial visual alignment of brake shoe 50 as hereinafter described.

Operation of the device is as follows. With the brake shoe 50 within the range of sizes receivable upon the device, a rough setting is obtained by disposing the shoe Within clamp units 2| and 22 with the shoe 50 in vertical alignment with the scribe lines 86 on base plate Il?. With clamp members 2| and 22 temporarily tightened, carriage I5 is rotated to a position whereby the cutter blade 6|) may engage the surface of brake shoe 50 beneath the brake lining 5|. For this purpose a small portion of the lining may be removed from the shoe or the shoe may be positioned in a manner to allow the knife to engage the shoe surface at the extreme left end thereof as shown in Fig. 1. Both clamping bolts 61 and 'Il have been loosened prior to this stage, but upon obtaining the proper adjustment of blade 60, the bolts are tightened in a manner to insure light contact of blade (it upon the outer surface of brake shoe 50 and in tangential relation thereto. Scribe is then rotated to the vicinity of blade El) and is readily adjusted with the pointer 85 in vertical registry with the cutter edge of blade 6D, and set screw E4 tightened. Since the scribe pointer provides, as it is rotated about pintle I6, an accurate measurement of the radial dimension between the axisof pintle I6 and the cutting edge of blade 60, the scribe is rotated to the opposite end of shoe Sii and with one or both of the clamp assemblies 2| and 22 slightly loosened, the free end of shoe 50 is brought into vertical alignment with the scribe while the opposite end of the shoe is maintained in light engaging Contact with blade 60. Clamp assemblies 2| and 22 are then securely tightened. The device is now ready for manual rotation, in a counter-clockwise direction as viewed in the drawings, for the rapid removal of lining 5| from slice 50.

Since the scribe does not require re-setting for subsequent shoes of the same circumferential arc, a complete set of brake linings may rapidly be removed from their shoes in the manner above described.

6 "Whatlis claimed is: 'Le-Apparatusf-for removing brake lining `from arcuate shoes comprising a rotatable fcarriage having a circular edge portion defining an arc of 1 not over18'0','means*for mounting a shoe'y in detachable clamped' 'engagement with said edge portion,A afiknife blade having means for adjustably moi-inting-said knife blade in a pcstiontangent toftheiedgeof said shoe mounted on the. carriage and Avn'ieansuto lock said knife blade in said position, lug stop means extending outwardly of said edge portion, and a handle integral with said carriage whereby said carriage is rotatable to permit said blade to peel said brake lining from said shoe.

2. In a device of the character described, a base plate, a pintle member supported by said base plate to extend perpendicularly therefrom, a carriage having a circular edge portion defining an arc of not over supported by said pintle member for rotation with respect to said base plate, stop lug means at one end of and extending outwardly from said circular edge portion, handle means integral with said carriage,

means for clamping a brake shoe to said edge portion in a position concentric with said pintle member, and knife means mounted on said base plate, with a blade tangent to the edge of said brake shoe said knife means being mounted on a knife holder adapted to have sliding movement in a groove extending toward said pintle. said knife holder comprising a pair of block members rotatable with respect to each other, and means to lock said knife holder in a said groove and to lock said knife member holderagainst rotation.

3. In apparatus for removing brake lining from arcuate shoes, the combination comprising a base plate, a carriage having a circular` edge defining an arc not over 130 rotatably mounted in respect to said plate, means for clamping a brake shoe to said edge, knife means with a blade tangent to the edge of said brake shoe mounted on said plate and adjustable radiallt7 of the axis of said carriage, means to lock said knife means in position, stop lug means at one end of and extending outwardly from said circular edge, and a handle integral with said carriage whereby said carriage is rotatable with respect to said knife means.

4. In apparatus for removing brake lining from arcuate shoes, the combination comprising a base plate, a carriage having a circular edge dening an arc not over rotatably mounted in respect to said plate, means for clamping a brake shoe to said edge, knife means with a blade tangent to the edge of said brake shoe mounted on said plate and adjustable radially of the axis of said carriage, means to lock said knife means in position, stop lug means at one end of and extending outwardly from said circular edge, and a handle on said carriage whereby said carriage is rotatable with respect to said knife means.

5. Apparatus for removing brake lining from arcuate shoes comprising a rotatable carriage having a circular edge portion defining an arc of not over 180, means for mounting a shoe in detachable clamped engagement with said edge portion, a knife blade having means for adjustably mounting said Yknife blade in a position tangent to the edge of said shoe mounted on the carriage and means to lock said knife blade in said position, lug stop means extending outwardly of saidedge portion and a handle on 7 said carriage whereby said carriage is rotatable Number to permit said blade to peel said brake lining 442,399 from said shoe. 1,515,636 1,609,514 References Cited in the le of this patent 5 1,653,104 UNITED STATES PATENTS 1,723,356

Number Name Date 30,736 Keen Nov. 27, 1860 2359677 100,771 Kavanagh Mar. 15, 1870 397,181 Gorham Feb. 5, 1889 1 8 Name Date Salford Dec. 9, 1890 Wagner Nov. 18, 1924 Kimmerling Dec. 7, 1925 Kimmerling Dec. 20, 1927 Knowles Aug. 6, 1929 Mays Apr. 18, 1944: Tilden Sept. 19, 1944 Reeves Oct. 3, 194,4 

